MIC5247 Micrel, Inc. MIC5247 150mA Low-Voltage µCap Linear Regulator General Description Features The MIC5247 is an efficient and precise, low-voltage CMOS voltage regulator optimized for ultra-low noise applications. The MIC5247 offers better than 1% initial accuracy and 85µA constant ground current over load (typically 85µA). The MIC5247 provides a very low-noise output, ideal for RF applications where quiet voltage sources are required. A noise bypass pin is also available for further reduction of output noise. • • • • • • • • • • • Designed specifically for handheld and battery-powered devices, the MIC5247 provides a logic compatible enable pin. When disabled, power consumption drops nearly to zero. Ultra-low noise Low-voltage outputs Load independent, ultra-low ground current: 85µA 150mA output current Current limiting Thermal shutdown Tight load and line regulation “Zero” off-mode current Stability with low-ESR capacitors Fast transient response Logic-controlled enable input Applications The MIC5247 also works with low-ESR ceramic capacitors, reducing the amount of board space necessary for power applications, critical in handheld wireless devices. • • • • • • • • Key features include current limit, thermal shutdown, a pushpull output for faster transient response, and an active clamp to speed up device turnoff. Available in the 6-pin 2mm × 2mm MLF™ package and the IttyBitty® SOT-23-5 package, the MIC5247 also offers a range of fixed output voltages. All support documentation can be found on Micrel’s web site at www.micrel.com. Cellular phones and pagers Cellular accessories Battery-powered equipment Laptop, notebook, and palmtop computers PCMCIA VCC and VPP regulation/switching Consumer/personal electronics SMPS post-regulator/DC-to-DC modules High-efficiency linear power supplies Typical Application VIN MIC5247-x.xBM5 1 5 2 Enable Shutdown 3 EN EN (pin 3) may be connected directly to IN (pin 1). 4 VIN VOUT COUT ENABLE SHUTDOWN EN CBYP (optional) VOUT MIC5247-x.xBML 1 6 2 5 3 4 CBYP COUT (optional) Ultra-Low-Noise Regulator Application Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com February 2006 1 M9999-022406 MIC5247 Micrel, Inc. Ordering Information Part Number Standard Marking Pb-Free Marking** Voltage* Junction Temp. Range Package MIC5247-1.5BM5 LU15 MIC5247-1.5YM5 LU15 1.5V –40ºC to +125ºC SOT-23-5 MIC5247-1.6BM5 LU16 MIC5247-1.6YM5 LU16 1.6V –40ºC to +125ºC SOT-23-5 MIC5247-1.8BM5 LU18 MIC5247-1.8YM5 LU18 1.8V –40ºC to +125ºC SOT-23-5 MIC5247-1.85BM5 LU1J MIC5247-1.85YM5 LU1J 1.85V –40ºC to +125ºC SOT-23-5 MIC5247-2.0BM5 LU20 MIC5247-2.0YM5 LU20 2.0V –40ºC to +125ºC SOT-23-5 MIC5247-2.1BM5 LU21 MIC5247-2.1YM5 LU21 2.1V –40ºC to +125ºC SOT-23-5 MIC5247-2.2BM5 LU22 MIC5247-2.2YM5 LU22 2.2V –40ºC to +125ºC SOT-23-5 MIC5247-2.4BM5 LU24 MIC5247-2.4YM5 LU24 2.4V –40ºC to +125ºC SOT-23-5 MIC5247-1.8BD5 NU18 MIC5247-1.8YD5 NU18 1.8V –40ºC to +125ºC Thin SOT-23-5 MIC5247-2.0BD5 NU20 MIC5247-2.0YD5 NU20 2.0V –40ºC to +125ºC Thin SOT-23-5 MIC5247-1.5BML U15 MIC5247-1.5YML U15 1.5V –40ºC to +125ºC 6-Pin 2mm x 2mm MLF™ MIC5247-1.6BML U16 MIC5247-1.6YML U16 1.6V –40ºC to +125ºC 6-Pin 2mm x 2mm MLF™ MIC5247-1.8BML U18 MIC5247-1.8YML U18 1.8V –40ºC to +125ºC 6-Pin 2mm x 2mm MLF™ MIC5247-1.85BML U1J MIC5247-1.85YML U1J 1.85V –40ºC to +125ºC 6-Pin 2mm x 2mm MLF™ * Other voltage options available, please contact Micrel Marketing for details. ** Over and under bar ( ) (__) symbols may not be to scale. Pin Configuration EN GND IN 2 3 EN 1 1 LUxx/ NUxx GND 2 4 5 BYP OUT IN 3 6 BYP 5 NC 4 OUT MIC5247-x.xBML / YML 6-Pin 2mm × 2mm MLF™ (ML) (Top View) MIC5247-x.xBM5 / YM5 MIC5247-x.xBD5 / YM5 (Top View) Pin Description Pin Number SOT-23-5 Pin Number MLF™-6 Pin Name 1 3 IN 2 2 GND 3 1 EN Enable/Shutdown (Input): CMOS-compatible input. Logic high = enable; logic low = shutdown. Do not leave open. 4 6 BYP Reference bypass: Connect external 0.01pF capacitor to GND to reduce output noise. May be left open. 5 4 OUT Regulator output. — 5 NC — EP GND M9999-022406 Pin Function Supply input. Ground. No internal connection. Ground. Internally connected to the exposed pad. Connect to ground pin. 2 February 2006 MIC5247 Micrel, Inc. Absolute Maximum Ratings(1) Operating Ratings(2) Supply Input Voltage (VIN) ....................................0V to +7V Enable Input Voltage (VEN) ...................................0V to VIN Junction Temperature (TJ) ....................................... +150°C Storage Temperature (TS) ........................ –65°C to +150°C Lead Temperature (soldering, 5 sec.) ........................ 260°C ESD Rating(3) Input Voltage (VIN) .......................................... +2.7V to +6V Enable Input Voltage (VEN) ...................................0V to VIN Junction Temperature (TJ) ........................ –40°C to +125°C Package Thermal Resistance SOT-23-5 (θJA) .................................................. 235°C/W 2mm × 2mm MLF™ (θJA) .................................... 90°C/W Electrical Characteristics(4) VIN = VOUT + 1.0V; VIN = VEN; IOUT = 100µA; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted. Symbol Parameter Conditions Min VO Output Voltage Accuracy IOUT = 0mA –1 –2 ΔVLNR Line Regulation VIN = 2.7V to 6V ΔVLDR VIN – VOUT IQ Load Regulation Load Regulation for 1.5V and 1.6V Dropout Voltage Quiescent Current IGND Ground Pin Current(7) PSRR Power Supply Rejection ILIM –0.3 IOUT = 0.1mA to 150mA(5) IOUT = 0.1mA to 150mA, VOUT = 1.5V or 1.6V Max Units 1 2 % % +0.3 %/V 2 3 % 3 4 % IOUT = 150mA(6) 150 0.2 1 µA IOUT = 0mA 85 150 µA 85 150 f ≤ 1kHz 50 VEN ≤ 0.4V (shutdown) IOUT = 150mA VOUT = 0V 160 mV µA dB 300 mA Output Voltage Noise COUT = 10µF, CBYP = 0.01µF, f = 10Hz to 100kHz 30 µVrms VIL Enable Input Logic-Low Voltage VIN = 2.7V to 5.5V, regulator shutdown 0.8 IEN Enable Input Current en Current Limit Typ Enable Input VIH Enable Input Logic-High Voltage 1.6 V 1 V 0.01 µA 0.01 µA 500 Ω Thermal Shutdown Temperature 150 °C Thermal Shutdown Hysteresis 10 °C Shutdown Resistance Discharge VIN = 2.7V to 5.5V, regulator enabled 0.4 VIL ≤ 0.4V VIH ≥ 1.6V Thermal Protection Notes: 1. Exceeding the absolute maximum ratings may damage the device. 2. The device is not guaranteed to function outside its operating ratings. 3. Devices are ESD sensitive. Handling precautions recommended. 4. Specification for packaged product only. 5. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load range from 0.1mA to 150mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification. 6. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 2% below its nominal value measured a1V differential. For outputs below 2.7V, dropout voltage is the input-to-output voltage differential with the minimum input voltage 2.7V. Minimum input operating voltage is 2.7V. 7. Ground pin current is the regulator quiescent current plus pass transistor base current. The total current drawn from the supply is the sum of the load current plus the ground pin current. February 2006 3 M9999-022406 MIC5247 Micrel, Inc. Typical Characteristics 40 20 ILOAD = 100µA 0 -40 -10 20 50 80 110 140 TEMPERATURE °C) ( 40 PSRR (dB) ILOAD = 150mA 1 2 3 INPUT VOLTAGE (V) 4 100 80 60 40 20 ILOAD = 150mA Dropout Characteristics ILOAD = 100µA 1x106 1x105 1x104 1x103 1x102 1x103 1x10 2 OUTPUT CURRENT (mA) Ground Pin Current 80 60 40 20 0 -40 -10 20 50 80 110 140 TEMPERATURE °C) ( 0 0 VIN = VOUT + 1 70 Ground Pin Current 0 0 500 ILOAD = 100µA 2 3 1 INPUT VOLTAGE (V) 4 Short Circuit Current vs. Temperature 400 ILOAD = 150mA 300 200 1 20 1x10 71 ILOAD = 50mA 1k 10k 100k 1M 100 FREQUENCY (Hz) 2 60 1 1x101 10 3 80 M9999-022406 1x10 72 CBYP = 0.01 F VIN = 2.8V VOUT = 1.8V COUT = 4.7 F VOLTAGE OUT (V) GROUND CURRENT (µA) Ground Pin Current 74 73 100 60 0 0 -8 Ground Pin Current 80 100 CBYP = 0 GROUND CURRENT (µA) GROUND CURRENT (µA) 100 75 1x10-6 1x10-7 Ground Current vs. Output Current 1x101 FREQUENCY (Hz) 1x10 FREQUENCY (Hz) 1x100 20 IL = 150mA VIN = 3.4V 10 VOUT = 2.4V COUT = 10 F Ceramic 0 10 100 1k 10k 100k 1M Noise Performance -5 1x10 CBYP = 0 FREQUENCY (Hz) CBYP = 0 20 IL = 100mA VIN = 3.4V 10 V OUT = 2.4V COUT = 10µF Ceramic 0 GROUND CURRENT (µA) 30 30 -1 1 F CBYP = 0 IL = 50mA 20 VIN = 3.4V 10 VOUT = 2.4V COUT =10µF Ceramic 0 30 GROUND CURRENT (µA) 0.01 F OUTPUT SPECTRAL NOISE DENSITY ( V/rt Hz) PSRR (dB) 40 FREQUENCY (Hz) Power Supply Rejection Ratio 60 50 1x102 1x101 0 1x106 10 1x105 20 1x104 IL = 100µA VIN = 3.4V VOUT = 2.4V COUT = 10µF Ceramic 30 0.01µF 1µF 40 40 SHORT CIRCUIT CURRENT (mA) 40 50 0.01µF 1x106 50 =0 50 1x105 BYP PSRR (dB) 60 C 1x103 PSRR (dB) 70 Power Supply Rejection Ratio 60 1µF 60 1x104 CBYP = 0.01µF 1x103 80 CBYP = 1µF Power Supply Rejection Ratio 70 1x102 Power Supply Rejection Ratio 90 100 1 2 3 INPUT VOLTAGE (V) 4 4 VOUT = 0 0 -40 -10 20 50 80 110 140 TEMPERATURE °C) ( February 2006 MIC5247 Micrel, Inc. Typical Characteristics, cont. COUT = 10µF ILOAD = 100mA 0 1x10-5 2.3 -40 -10 20 50 80 110 140 TEMPERATURE °C) ( Prop Delay 5 1x101 ILOAD = 100µA 1x100 50 Rise Time 1x10-3 100 1x10-4 TIME (µs) 150 2.4 February 2006 Turn-On Time vs. Bypass Capacitance 1x10-1 200 1x10-2 Output Voltage vs. Temperature OUTPUT VOLTAGE (V) 2.5 BYPASS CAPACITOR(µF) M9999-022406 MIC5247 Micrel, Inc. Functional Characteristics Load Transient Response Line Transient Response 4.4V COUT = 10µF CBYP = 0 VIN = 3.4V VOUT = 2.4V 3.4V COUT = 10µF VOUT = 2.4V ILOAD = 100µA 100mA 100µA TIME (100µs/div.) M9999-022406 TIME (500µs/div.) 6 February 2006 MIC5247 Micrel, Inc. Block Diagram IN Reference Voltage Startup/ Shutdown Control Quickstart/ Noise Cancellation EN BYP Thermal Sensor Undervoltage Lockout PU L L UP FAUL T Error Amplifier Current Amplifier OUT PU L L DOWN AC TIVE SH U TD OWN GND February 2006 7 M9999-022406 MIC5247 Micrel, Inc. Applications Information resistance of the device and the following basic equation: T (max) − T A PD (max) = J θJA Enable/Shutdown The MIC5247 comes with an active-high enable pin that can disable the regulator. Forcing the enable pin low disables the regulator and sends it into a “zero” off-mode-current state. In this state, current consumed by the regulator goes nearly to zero. Forcing the enable pin high enables the output voltage. This part is CMOS and the enable pin cannot be left floating; a floating enable pin may cause an indeterminate state on the output. TJ(max) is the maximum junction temperature of the die, 125°C, and TA is the ambient operating temperature. θJA is layout dependent; Table 1 shows examples of junction-toambient thermal resistance for the MIC5247. Package Input Capacitor θJA 1” Square Copper Clad θJC 235°C/W 185°C/W 145°C/W SOT-23-5 (M5) An input capacitor is not required for stability. A 1µF input capacitor is recommended when the bulk AC supply capacitance is more than 10 inches away from the device, or when the supply is a battery. Table 1. SOT-23-5 Thermal Resistance The actual power dissipation of the regulator circuit can be determined using the equation: ( Output Capacitor ) PD = VIN − VOUT × IOUT + VIN × IGND The MIC5247 requires an output capacitor for stability. The design requires 1µF or greater on the output to maintain stability. The capacitor can be a low-ESR ceramic chip capacitor. The MIC5247 has been designed to work specifically with low-cost, small chip capacitors. Tantalum capacitors can also be used for improved capacitance over temperature. The value of the capacitor can be increased without bound. Substituting PD(max) for PD and solving for the operating conditions that are critical to the application will give the maximum operating conditions for the regulator circuit. For example, when operating the MIC5247-2.4BM5 at room temperature with a minimum footprint layout, the maximum input voltage for a set output current can be determined as follows: Bypass Capacitor 125°C − 25 °C PD (max) = 235°C /W PD (max) = 425mW A capacitor can be placed from the noise bypass pin to ground to reduce output voltage noise. The capacitor bypasses the internal reference. A 0.01µF capacitor is recommended for applications that require low-noise outputs. The junction-to-ambient thermal resistance for the minimum footprint is 235°C/W, from Table 1. The maximum power dissipation must not be exceeded for proper operation. Using the output voltage of 2.4V and an output current of 150mA, the maximum input voltage can be determined. Because this device is CMOS and the ground current is typically 100µA over the load range, the power dissipation contributed by the ground current is < 1% and can be ignored for this calculation. The bypass capacitor can be increased without bound, further reducing noise and improving PSRR. Turn-on time remains constant with respect to bypass capacitance. Refer to the “Typical Characteristics” section for a graph of turn-on time vs. bypass capacitor. Transient Response The MIC5247 implements a unique output stage to dramatically improve transient response recovery time. The output is a totem-pole configuration with a P-Channel MOSFET pass device and an N-Channel MOSFET clamp. The N-Channel clamp is a significantly smaller device that prevents the output voltage from overshooting when a heavy load is removed. This feature helps to speed up the transient response by significantly decreasing transient response recovery time during the transition from heavy load (100mA) to light load (85µA). 425mW = (VIN – 2.4V) 150mA 425mW = VIN ×150mA – 360mW 785mW = VIN×150mA VIN(max) = 5.2V Therefore, a 2.4V application at 150mA of output current can accept a maximum input voltage of 5.2V in a SOT-23-5 package. For a full discussion of heat sinking and thermal effects on voltage regulators, refer to the “Regulator Thermals” section of Micrel’s Designing with Low-Dropout Voltage Regulators handbook. Active Shutdown The MIC5247 also features an active shutdown clamp, which is an N-Channel MOSFET that turns on when the device is disabled. This allows the output capacitor and load to discharge, de-energizing the load. Fixed Regulator Applications VIN MIC5247-x.xBM5 1 5 2 Thermal Considerations 3 The MIC5247 is designed to provide 150mA of continuous current in a very small package. Maximum power dissipation can be calculated based on the output current and the voltage drop across the part. To determine the maximum power dissipation of the package, use the junction-to-ambient thermal M9999-022406 θJA Recommended Minimum Footprint VOU T 1µF 4 0.01µF Figure 1. Ultra-Low-Noise Fixed Voltage Application 8 February 2006 MIC5247 Micrel, Inc. Figure 1 includes a 0.01µF capacitor for low-noise operation and shows EN (pin 3) connected to IN (pin 1) for an application where enable/shutdown is not required. COUT = 1µF minimum. VIN MIC5247-x.xBM5 VOU T 1 5 2 Enable Shutdown 3 4 1.0µF EN Figure 2. Low-Noise Fixed Voltage Application Figure 2 is an example of a low-noise configuration where CBYP is not required. COUT = 1µF minimum. February 2006 9 M9999-022406 MIC5247 Micrel, Inc. Package Information SOT-23-5 (M) TSOT-23-5 (D5) M9999-022406 10 February 2006 MIC5247 Micrel, Inc. 6-Pin MLF™ (ML) MICREL, INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB http://www.micrel.com The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2004 Micrel, Incorporated. February 2006 11 M9999-022406